Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * Copyright (C) 2003 Christophe Saout <christophe@saout.de> | |
3 | * Copyright (C) 2004 Clemens Fruhwirth <clemens@endorphin.org> | |
3f1e9070 | 4 | * Copyright (C) 2006-2008 Red Hat, Inc. All rights reserved. |
1da177e4 LT |
5 | * |
6 | * This file is released under the GPL. | |
7 | */ | |
8 | ||
43d69034 | 9 | #include <linux/completion.h> |
d1806f6a | 10 | #include <linux/err.h> |
1da177e4 LT |
11 | #include <linux/module.h> |
12 | #include <linux/init.h> | |
13 | #include <linux/kernel.h> | |
14 | #include <linux/bio.h> | |
15 | #include <linux/blkdev.h> | |
16 | #include <linux/mempool.h> | |
17 | #include <linux/slab.h> | |
18 | #include <linux/crypto.h> | |
19 | #include <linux/workqueue.h> | |
3fcfab16 | 20 | #include <linux/backing-dev.h> |
1da177e4 | 21 | #include <asm/atomic.h> |
378f058c | 22 | #include <linux/scatterlist.h> |
1da177e4 | 23 | #include <asm/page.h> |
48527fa7 | 24 | #include <asm/unaligned.h> |
1da177e4 | 25 | |
586e80e6 | 26 | #include <linux/device-mapper.h> |
1da177e4 | 27 | |
72d94861 | 28 | #define DM_MSG_PREFIX "crypt" |
e48d4bbf | 29 | #define MESG_STR(x) x, sizeof(x) |
1da177e4 | 30 | |
1da177e4 LT |
31 | /* |
32 | * context holding the current state of a multi-part conversion | |
33 | */ | |
34 | struct convert_context { | |
43d69034 | 35 | struct completion restart; |
1da177e4 LT |
36 | struct bio *bio_in; |
37 | struct bio *bio_out; | |
38 | unsigned int offset_in; | |
39 | unsigned int offset_out; | |
40 | unsigned int idx_in; | |
41 | unsigned int idx_out; | |
42 | sector_t sector; | |
43d69034 | 43 | atomic_t pending; |
1da177e4 LT |
44 | }; |
45 | ||
53017030 MB |
46 | /* |
47 | * per bio private data | |
48 | */ | |
49 | struct dm_crypt_io { | |
50 | struct dm_target *target; | |
51 | struct bio *base_bio; | |
52 | struct work_struct work; | |
53 | ||
54 | struct convert_context ctx; | |
55 | ||
56 | atomic_t pending; | |
57 | int error; | |
0c395b0f | 58 | sector_t sector; |
393b47ef | 59 | struct dm_crypt_io *base_io; |
53017030 MB |
60 | }; |
61 | ||
01482b76 | 62 | struct dm_crypt_request { |
b2174eeb | 63 | struct convert_context *ctx; |
01482b76 MB |
64 | struct scatterlist sg_in; |
65 | struct scatterlist sg_out; | |
66 | }; | |
67 | ||
1da177e4 LT |
68 | struct crypt_config; |
69 | ||
70 | struct crypt_iv_operations { | |
71 | int (*ctr)(struct crypt_config *cc, struct dm_target *ti, | |
d469f841 | 72 | const char *opts); |
1da177e4 LT |
73 | void (*dtr)(struct crypt_config *cc); |
74 | const char *(*status)(struct crypt_config *cc); | |
75 | int (*generator)(struct crypt_config *cc, u8 *iv, sector_t sector); | |
76 | }; | |
77 | ||
78 | /* | |
79 | * Crypt: maps a linear range of a block device | |
80 | * and encrypts / decrypts at the same time. | |
81 | */ | |
e48d4bbf | 82 | enum flags { DM_CRYPT_SUSPENDED, DM_CRYPT_KEY_VALID }; |
1da177e4 LT |
83 | struct crypt_config { |
84 | struct dm_dev *dev; | |
85 | sector_t start; | |
86 | ||
87 | /* | |
ddd42edf MB |
88 | * pool for per bio private data, crypto requests and |
89 | * encryption requeusts/buffer pages | |
1da177e4 LT |
90 | */ |
91 | mempool_t *io_pool; | |
ddd42edf | 92 | mempool_t *req_pool; |
1da177e4 | 93 | mempool_t *page_pool; |
6a24c718 | 94 | struct bio_set *bs; |
1da177e4 | 95 | |
cabf08e4 MB |
96 | struct workqueue_struct *io_queue; |
97 | struct workqueue_struct *crypt_queue; | |
3f1e9070 | 98 | |
1da177e4 LT |
99 | /* |
100 | * crypto related data | |
101 | */ | |
102 | struct crypt_iv_operations *iv_gen_ops; | |
103 | char *iv_mode; | |
79066ad3 HX |
104 | union { |
105 | struct crypto_cipher *essiv_tfm; | |
106 | int benbi_shift; | |
107 | } iv_gen_private; | |
1da177e4 LT |
108 | sector_t iv_offset; |
109 | unsigned int iv_size; | |
110 | ||
ddd42edf MB |
111 | /* |
112 | * Layout of each crypto request: | |
113 | * | |
114 | * struct ablkcipher_request | |
115 | * context | |
116 | * padding | |
117 | * struct dm_crypt_request | |
118 | * padding | |
119 | * IV | |
120 | * | |
121 | * The padding is added so that dm_crypt_request and the IV are | |
122 | * correctly aligned. | |
123 | */ | |
124 | unsigned int dmreq_start; | |
125 | struct ablkcipher_request *req; | |
126 | ||
d1806f6a HX |
127 | char cipher[CRYPTO_MAX_ALG_NAME]; |
128 | char chainmode[CRYPTO_MAX_ALG_NAME]; | |
3a7f6c99 | 129 | struct crypto_ablkcipher *tfm; |
e48d4bbf | 130 | unsigned long flags; |
1da177e4 LT |
131 | unsigned int key_size; |
132 | u8 key[0]; | |
133 | }; | |
134 | ||
6a24c718 | 135 | #define MIN_IOS 16 |
1da177e4 LT |
136 | #define MIN_POOL_PAGES 32 |
137 | #define MIN_BIO_PAGES 8 | |
138 | ||
e18b890b | 139 | static struct kmem_cache *_crypt_io_pool; |
1da177e4 | 140 | |
028867ac | 141 | static void clone_init(struct dm_crypt_io *, struct bio *); |
395b167c | 142 | static void kcryptd_queue_crypt(struct dm_crypt_io *io); |
027581f3 | 143 | |
1da177e4 LT |
144 | /* |
145 | * Different IV generation algorithms: | |
146 | * | |
3c164bd8 | 147 | * plain: the initial vector is the 32-bit little-endian version of the sector |
3a4fa0a2 | 148 | * number, padded with zeros if necessary. |
1da177e4 | 149 | * |
3c164bd8 RS |
150 | * essiv: "encrypted sector|salt initial vector", the sector number is |
151 | * encrypted with the bulk cipher using a salt as key. The salt | |
152 | * should be derived from the bulk cipher's key via hashing. | |
1da177e4 | 153 | * |
48527fa7 RS |
154 | * benbi: the 64-bit "big-endian 'narrow block'-count", starting at 1 |
155 | * (needed for LRW-32-AES and possible other narrow block modes) | |
156 | * | |
46b47730 LN |
157 | * null: the initial vector is always zero. Provides compatibility with |
158 | * obsolete loop_fish2 devices. Do not use for new devices. | |
159 | * | |
1da177e4 LT |
160 | * plumb: unimplemented, see: |
161 | * http://article.gmane.org/gmane.linux.kernel.device-mapper.dm-crypt/454 | |
162 | */ | |
163 | ||
164 | static int crypt_iv_plain_gen(struct crypt_config *cc, u8 *iv, sector_t sector) | |
165 | { | |
166 | memset(iv, 0, cc->iv_size); | |
167 | *(u32 *)iv = cpu_to_le32(sector & 0xffffffff); | |
168 | ||
169 | return 0; | |
170 | } | |
171 | ||
172 | static int crypt_iv_essiv_ctr(struct crypt_config *cc, struct dm_target *ti, | |
d469f841 | 173 | const char *opts) |
1da177e4 | 174 | { |
d1806f6a | 175 | struct crypto_cipher *essiv_tfm; |
35058687 HX |
176 | struct crypto_hash *hash_tfm; |
177 | struct hash_desc desc; | |
1da177e4 LT |
178 | struct scatterlist sg; |
179 | unsigned int saltsize; | |
180 | u8 *salt; | |
d1806f6a | 181 | int err; |
1da177e4 LT |
182 | |
183 | if (opts == NULL) { | |
72d94861 | 184 | ti->error = "Digest algorithm missing for ESSIV mode"; |
1da177e4 LT |
185 | return -EINVAL; |
186 | } | |
187 | ||
188 | /* Hash the cipher key with the given hash algorithm */ | |
35058687 HX |
189 | hash_tfm = crypto_alloc_hash(opts, 0, CRYPTO_ALG_ASYNC); |
190 | if (IS_ERR(hash_tfm)) { | |
72d94861 | 191 | ti->error = "Error initializing ESSIV hash"; |
35058687 | 192 | return PTR_ERR(hash_tfm); |
1da177e4 LT |
193 | } |
194 | ||
35058687 | 195 | saltsize = crypto_hash_digestsize(hash_tfm); |
1da177e4 LT |
196 | salt = kmalloc(saltsize, GFP_KERNEL); |
197 | if (salt == NULL) { | |
72d94861 | 198 | ti->error = "Error kmallocing salt storage in ESSIV"; |
35058687 | 199 | crypto_free_hash(hash_tfm); |
1da177e4 LT |
200 | return -ENOMEM; |
201 | } | |
202 | ||
68e3f5dd | 203 | sg_init_one(&sg, cc->key, cc->key_size); |
35058687 HX |
204 | desc.tfm = hash_tfm; |
205 | desc.flags = CRYPTO_TFM_REQ_MAY_SLEEP; | |
206 | err = crypto_hash_digest(&desc, &sg, cc->key_size, salt); | |
207 | crypto_free_hash(hash_tfm); | |
208 | ||
209 | if (err) { | |
210 | ti->error = "Error calculating hash in ESSIV"; | |
815f9e32 | 211 | kfree(salt); |
35058687 HX |
212 | return err; |
213 | } | |
1da177e4 LT |
214 | |
215 | /* Setup the essiv_tfm with the given salt */ | |
d1806f6a HX |
216 | essiv_tfm = crypto_alloc_cipher(cc->cipher, 0, CRYPTO_ALG_ASYNC); |
217 | if (IS_ERR(essiv_tfm)) { | |
72d94861 | 218 | ti->error = "Error allocating crypto tfm for ESSIV"; |
1da177e4 | 219 | kfree(salt); |
d1806f6a | 220 | return PTR_ERR(essiv_tfm); |
1da177e4 | 221 | } |
d1806f6a | 222 | if (crypto_cipher_blocksize(essiv_tfm) != |
3a7f6c99 | 223 | crypto_ablkcipher_ivsize(cc->tfm)) { |
72d94861 | 224 | ti->error = "Block size of ESSIV cipher does " |
d469f841 | 225 | "not match IV size of block cipher"; |
d1806f6a | 226 | crypto_free_cipher(essiv_tfm); |
1da177e4 LT |
227 | kfree(salt); |
228 | return -EINVAL; | |
229 | } | |
d1806f6a HX |
230 | err = crypto_cipher_setkey(essiv_tfm, salt, saltsize); |
231 | if (err) { | |
72d94861 | 232 | ti->error = "Failed to set key for ESSIV cipher"; |
d1806f6a | 233 | crypto_free_cipher(essiv_tfm); |
1da177e4 | 234 | kfree(salt); |
d1806f6a | 235 | return err; |
1da177e4 LT |
236 | } |
237 | kfree(salt); | |
238 | ||
79066ad3 | 239 | cc->iv_gen_private.essiv_tfm = essiv_tfm; |
1da177e4 LT |
240 | return 0; |
241 | } | |
242 | ||
243 | static void crypt_iv_essiv_dtr(struct crypt_config *cc) | |
244 | { | |
79066ad3 HX |
245 | crypto_free_cipher(cc->iv_gen_private.essiv_tfm); |
246 | cc->iv_gen_private.essiv_tfm = NULL; | |
1da177e4 LT |
247 | } |
248 | ||
249 | static int crypt_iv_essiv_gen(struct crypt_config *cc, u8 *iv, sector_t sector) | |
250 | { | |
1da177e4 LT |
251 | memset(iv, 0, cc->iv_size); |
252 | *(u64 *)iv = cpu_to_le64(sector); | |
79066ad3 | 253 | crypto_cipher_encrypt_one(cc->iv_gen_private.essiv_tfm, iv, iv); |
1da177e4 LT |
254 | return 0; |
255 | } | |
256 | ||
48527fa7 RS |
257 | static int crypt_iv_benbi_ctr(struct crypt_config *cc, struct dm_target *ti, |
258 | const char *opts) | |
259 | { | |
3a7f6c99 | 260 | unsigned bs = crypto_ablkcipher_blocksize(cc->tfm); |
f0d1b0b3 | 261 | int log = ilog2(bs); |
48527fa7 RS |
262 | |
263 | /* we need to calculate how far we must shift the sector count | |
264 | * to get the cipher block count, we use this shift in _gen */ | |
265 | ||
266 | if (1 << log != bs) { | |
267 | ti->error = "cypher blocksize is not a power of 2"; | |
268 | return -EINVAL; | |
269 | } | |
270 | ||
271 | if (log > 9) { | |
272 | ti->error = "cypher blocksize is > 512"; | |
273 | return -EINVAL; | |
274 | } | |
275 | ||
79066ad3 | 276 | cc->iv_gen_private.benbi_shift = 9 - log; |
48527fa7 RS |
277 | |
278 | return 0; | |
279 | } | |
280 | ||
281 | static void crypt_iv_benbi_dtr(struct crypt_config *cc) | |
282 | { | |
48527fa7 RS |
283 | } |
284 | ||
285 | static int crypt_iv_benbi_gen(struct crypt_config *cc, u8 *iv, sector_t sector) | |
286 | { | |
79066ad3 HX |
287 | __be64 val; |
288 | ||
48527fa7 | 289 | memset(iv, 0, cc->iv_size - sizeof(u64)); /* rest is cleared below */ |
79066ad3 HX |
290 | |
291 | val = cpu_to_be64(((u64)sector << cc->iv_gen_private.benbi_shift) + 1); | |
292 | put_unaligned(val, (__be64 *)(iv + cc->iv_size - sizeof(u64))); | |
48527fa7 | 293 | |
1da177e4 LT |
294 | return 0; |
295 | } | |
296 | ||
46b47730 LN |
297 | static int crypt_iv_null_gen(struct crypt_config *cc, u8 *iv, sector_t sector) |
298 | { | |
299 | memset(iv, 0, cc->iv_size); | |
300 | ||
301 | return 0; | |
302 | } | |
303 | ||
1da177e4 LT |
304 | static struct crypt_iv_operations crypt_iv_plain_ops = { |
305 | .generator = crypt_iv_plain_gen | |
306 | }; | |
307 | ||
308 | static struct crypt_iv_operations crypt_iv_essiv_ops = { | |
309 | .ctr = crypt_iv_essiv_ctr, | |
310 | .dtr = crypt_iv_essiv_dtr, | |
311 | .generator = crypt_iv_essiv_gen | |
312 | }; | |
313 | ||
48527fa7 RS |
314 | static struct crypt_iv_operations crypt_iv_benbi_ops = { |
315 | .ctr = crypt_iv_benbi_ctr, | |
316 | .dtr = crypt_iv_benbi_dtr, | |
317 | .generator = crypt_iv_benbi_gen | |
318 | }; | |
1da177e4 | 319 | |
46b47730 LN |
320 | static struct crypt_iv_operations crypt_iv_null_ops = { |
321 | .generator = crypt_iv_null_gen | |
322 | }; | |
323 | ||
d469f841 MB |
324 | static void crypt_convert_init(struct crypt_config *cc, |
325 | struct convert_context *ctx, | |
326 | struct bio *bio_out, struct bio *bio_in, | |
fcd369da | 327 | sector_t sector) |
1da177e4 LT |
328 | { |
329 | ctx->bio_in = bio_in; | |
330 | ctx->bio_out = bio_out; | |
331 | ctx->offset_in = 0; | |
332 | ctx->offset_out = 0; | |
333 | ctx->idx_in = bio_in ? bio_in->bi_idx : 0; | |
334 | ctx->idx_out = bio_out ? bio_out->bi_idx : 0; | |
335 | ctx->sector = sector + cc->iv_offset; | |
43d69034 | 336 | init_completion(&ctx->restart); |
1da177e4 LT |
337 | } |
338 | ||
b2174eeb HY |
339 | static struct dm_crypt_request *dmreq_of_req(struct crypt_config *cc, |
340 | struct ablkcipher_request *req) | |
341 | { | |
342 | return (struct dm_crypt_request *)((char *)req + cc->dmreq_start); | |
343 | } | |
344 | ||
345 | static struct ablkcipher_request *req_of_dmreq(struct crypt_config *cc, | |
346 | struct dm_crypt_request *dmreq) | |
347 | { | |
348 | return (struct ablkcipher_request *)((char *)dmreq - cc->dmreq_start); | |
349 | } | |
350 | ||
01482b76 | 351 | static int crypt_convert_block(struct crypt_config *cc, |
3a7f6c99 MB |
352 | struct convert_context *ctx, |
353 | struct ablkcipher_request *req) | |
01482b76 MB |
354 | { |
355 | struct bio_vec *bv_in = bio_iovec_idx(ctx->bio_in, ctx->idx_in); | |
356 | struct bio_vec *bv_out = bio_iovec_idx(ctx->bio_out, ctx->idx_out); | |
3a7f6c99 MB |
357 | struct dm_crypt_request *dmreq; |
358 | u8 *iv; | |
359 | int r = 0; | |
360 | ||
b2174eeb | 361 | dmreq = dmreq_of_req(cc, req); |
3a7f6c99 MB |
362 | iv = (u8 *)ALIGN((unsigned long)(dmreq + 1), |
363 | crypto_ablkcipher_alignmask(cc->tfm) + 1); | |
01482b76 | 364 | |
b2174eeb | 365 | dmreq->ctx = ctx; |
3a7f6c99 MB |
366 | sg_init_table(&dmreq->sg_in, 1); |
367 | sg_set_page(&dmreq->sg_in, bv_in->bv_page, 1 << SECTOR_SHIFT, | |
01482b76 MB |
368 | bv_in->bv_offset + ctx->offset_in); |
369 | ||
3a7f6c99 MB |
370 | sg_init_table(&dmreq->sg_out, 1); |
371 | sg_set_page(&dmreq->sg_out, bv_out->bv_page, 1 << SECTOR_SHIFT, | |
01482b76 MB |
372 | bv_out->bv_offset + ctx->offset_out); |
373 | ||
374 | ctx->offset_in += 1 << SECTOR_SHIFT; | |
375 | if (ctx->offset_in >= bv_in->bv_len) { | |
376 | ctx->offset_in = 0; | |
377 | ctx->idx_in++; | |
378 | } | |
379 | ||
380 | ctx->offset_out += 1 << SECTOR_SHIFT; | |
381 | if (ctx->offset_out >= bv_out->bv_len) { | |
382 | ctx->offset_out = 0; | |
383 | ctx->idx_out++; | |
384 | } | |
385 | ||
3a7f6c99 MB |
386 | if (cc->iv_gen_ops) { |
387 | r = cc->iv_gen_ops->generator(cc, iv, ctx->sector); | |
388 | if (r < 0) | |
389 | return r; | |
390 | } | |
391 | ||
392 | ablkcipher_request_set_crypt(req, &dmreq->sg_in, &dmreq->sg_out, | |
393 | 1 << SECTOR_SHIFT, iv); | |
394 | ||
395 | if (bio_data_dir(ctx->bio_in) == WRITE) | |
396 | r = crypto_ablkcipher_encrypt(req); | |
397 | else | |
398 | r = crypto_ablkcipher_decrypt(req); | |
399 | ||
400 | return r; | |
01482b76 MB |
401 | } |
402 | ||
95497a96 MB |
403 | static void kcryptd_async_done(struct crypto_async_request *async_req, |
404 | int error); | |
ddd42edf MB |
405 | static void crypt_alloc_req(struct crypt_config *cc, |
406 | struct convert_context *ctx) | |
407 | { | |
408 | if (!cc->req) | |
409 | cc->req = mempool_alloc(cc->req_pool, GFP_NOIO); | |
95497a96 MB |
410 | ablkcipher_request_set_tfm(cc->req, cc->tfm); |
411 | ablkcipher_request_set_callback(cc->req, CRYPTO_TFM_REQ_MAY_BACKLOG | | |
b2174eeb HY |
412 | CRYPTO_TFM_REQ_MAY_SLEEP, |
413 | kcryptd_async_done, | |
414 | dmreq_of_req(cc, cc->req)); | |
ddd42edf MB |
415 | } |
416 | ||
1da177e4 LT |
417 | /* |
418 | * Encrypt / decrypt data from one bio to another one (can be the same one) | |
419 | */ | |
420 | static int crypt_convert(struct crypt_config *cc, | |
d469f841 | 421 | struct convert_context *ctx) |
1da177e4 | 422 | { |
3f1e9070 | 423 | int r; |
1da177e4 | 424 | |
c8081618 MB |
425 | atomic_set(&ctx->pending, 1); |
426 | ||
1da177e4 LT |
427 | while(ctx->idx_in < ctx->bio_in->bi_vcnt && |
428 | ctx->idx_out < ctx->bio_out->bi_vcnt) { | |
1da177e4 | 429 | |
3a7f6c99 MB |
430 | crypt_alloc_req(cc, ctx); |
431 | ||
3f1e9070 MB |
432 | atomic_inc(&ctx->pending); |
433 | ||
3a7f6c99 MB |
434 | r = crypt_convert_block(cc, ctx, cc->req); |
435 | ||
436 | switch (r) { | |
3f1e9070 | 437 | /* async */ |
3a7f6c99 MB |
438 | case -EBUSY: |
439 | wait_for_completion(&ctx->restart); | |
440 | INIT_COMPLETION(ctx->restart); | |
441 | /* fall through*/ | |
442 | case -EINPROGRESS: | |
3a7f6c99 | 443 | cc->req = NULL; |
3f1e9070 MB |
444 | ctx->sector++; |
445 | continue; | |
446 | ||
447 | /* sync */ | |
3a7f6c99 | 448 | case 0: |
3f1e9070 | 449 | atomic_dec(&ctx->pending); |
3a7f6c99 | 450 | ctx->sector++; |
c7f1b204 | 451 | cond_resched(); |
3a7f6c99 | 452 | continue; |
3a7f6c99 | 453 | |
3f1e9070 MB |
454 | /* error */ |
455 | default: | |
456 | atomic_dec(&ctx->pending); | |
457 | return r; | |
458 | } | |
1da177e4 LT |
459 | } |
460 | ||
3f1e9070 | 461 | return 0; |
1da177e4 LT |
462 | } |
463 | ||
d469f841 MB |
464 | static void dm_crypt_bio_destructor(struct bio *bio) |
465 | { | |
028867ac | 466 | struct dm_crypt_io *io = bio->bi_private; |
6a24c718 MB |
467 | struct crypt_config *cc = io->target->private; |
468 | ||
469 | bio_free(bio, cc->bs); | |
d469f841 | 470 | } |
6a24c718 | 471 | |
1da177e4 LT |
472 | /* |
473 | * Generate a new unfragmented bio with the given size | |
474 | * This should never violate the device limitations | |
933f01d4 MB |
475 | * May return a smaller bio when running out of pages, indicated by |
476 | * *out_of_pages set to 1. | |
1da177e4 | 477 | */ |
933f01d4 MB |
478 | static struct bio *crypt_alloc_buffer(struct dm_crypt_io *io, unsigned size, |
479 | unsigned *out_of_pages) | |
1da177e4 | 480 | { |
027581f3 | 481 | struct crypt_config *cc = io->target->private; |
8b004457 | 482 | struct bio *clone; |
1da177e4 | 483 | unsigned int nr_iovecs = (size + PAGE_SIZE - 1) >> PAGE_SHIFT; |
b4e3ca1a | 484 | gfp_t gfp_mask = GFP_NOIO | __GFP_HIGHMEM; |
91e10625 MB |
485 | unsigned i, len; |
486 | struct page *page; | |
1da177e4 | 487 | |
2f9941b6 | 488 | clone = bio_alloc_bioset(GFP_NOIO, nr_iovecs, cc->bs); |
8b004457 | 489 | if (!clone) |
1da177e4 | 490 | return NULL; |
1da177e4 | 491 | |
027581f3 | 492 | clone_init(io, clone); |
933f01d4 | 493 | *out_of_pages = 0; |
6a24c718 | 494 | |
f97380bc | 495 | for (i = 0; i < nr_iovecs; i++) { |
91e10625 | 496 | page = mempool_alloc(cc->page_pool, gfp_mask); |
933f01d4 MB |
497 | if (!page) { |
498 | *out_of_pages = 1; | |
1da177e4 | 499 | break; |
933f01d4 | 500 | } |
1da177e4 LT |
501 | |
502 | /* | |
503 | * if additional pages cannot be allocated without waiting, | |
504 | * return a partially allocated bio, the caller will then try | |
505 | * to allocate additional bios while submitting this partial bio | |
506 | */ | |
f97380bc | 507 | if (i == (MIN_BIO_PAGES - 1)) |
1da177e4 LT |
508 | gfp_mask = (gfp_mask | __GFP_NOWARN) & ~__GFP_WAIT; |
509 | ||
91e10625 MB |
510 | len = (size > PAGE_SIZE) ? PAGE_SIZE : size; |
511 | ||
512 | if (!bio_add_page(clone, page, len, 0)) { | |
513 | mempool_free(page, cc->page_pool); | |
514 | break; | |
515 | } | |
1da177e4 | 516 | |
91e10625 | 517 | size -= len; |
1da177e4 LT |
518 | } |
519 | ||
8b004457 MB |
520 | if (!clone->bi_size) { |
521 | bio_put(clone); | |
1da177e4 LT |
522 | return NULL; |
523 | } | |
524 | ||
8b004457 | 525 | return clone; |
1da177e4 LT |
526 | } |
527 | ||
644bd2f0 | 528 | static void crypt_free_buffer_pages(struct crypt_config *cc, struct bio *clone) |
1da177e4 | 529 | { |
644bd2f0 | 530 | unsigned int i; |
1da177e4 LT |
531 | struct bio_vec *bv; |
532 | ||
644bd2f0 | 533 | for (i = 0; i < clone->bi_vcnt; i++) { |
8b004457 | 534 | bv = bio_iovec_idx(clone, i); |
1da177e4 LT |
535 | BUG_ON(!bv->bv_page); |
536 | mempool_free(bv->bv_page, cc->page_pool); | |
537 | bv->bv_page = NULL; | |
538 | } | |
539 | } | |
540 | ||
dc440d1e MB |
541 | static struct dm_crypt_io *crypt_io_alloc(struct dm_target *ti, |
542 | struct bio *bio, sector_t sector) | |
543 | { | |
544 | struct crypt_config *cc = ti->private; | |
545 | struct dm_crypt_io *io; | |
546 | ||
547 | io = mempool_alloc(cc->io_pool, GFP_NOIO); | |
548 | io->target = ti; | |
549 | io->base_bio = bio; | |
550 | io->sector = sector; | |
551 | io->error = 0; | |
393b47ef | 552 | io->base_io = NULL; |
dc440d1e MB |
553 | atomic_set(&io->pending, 0); |
554 | ||
555 | return io; | |
556 | } | |
557 | ||
3e1a8bdd MB |
558 | static void crypt_inc_pending(struct dm_crypt_io *io) |
559 | { | |
560 | atomic_inc(&io->pending); | |
561 | } | |
562 | ||
1da177e4 LT |
563 | /* |
564 | * One of the bios was finished. Check for completion of | |
565 | * the whole request and correctly clean up the buffer. | |
393b47ef | 566 | * If base_io is set, wait for the last fragment to complete. |
1da177e4 | 567 | */ |
5742fd77 | 568 | static void crypt_dec_pending(struct dm_crypt_io *io) |
1da177e4 | 569 | { |
5742fd77 | 570 | struct crypt_config *cc = io->target->private; |
b35f8caa MB |
571 | struct bio *base_bio = io->base_bio; |
572 | struct dm_crypt_io *base_io = io->base_io; | |
573 | int error = io->error; | |
1da177e4 LT |
574 | |
575 | if (!atomic_dec_and_test(&io->pending)) | |
576 | return; | |
577 | ||
b35f8caa MB |
578 | mempool_free(io, cc->io_pool); |
579 | ||
580 | if (likely(!base_io)) | |
581 | bio_endio(base_bio, error); | |
393b47ef | 582 | else { |
b35f8caa MB |
583 | if (error && !base_io->error) |
584 | base_io->error = error; | |
585 | crypt_dec_pending(base_io); | |
393b47ef | 586 | } |
1da177e4 LT |
587 | } |
588 | ||
589 | /* | |
cabf08e4 | 590 | * kcryptd/kcryptd_io: |
1da177e4 LT |
591 | * |
592 | * Needed because it would be very unwise to do decryption in an | |
23541d2d | 593 | * interrupt context. |
cabf08e4 MB |
594 | * |
595 | * kcryptd performs the actual encryption or decryption. | |
596 | * | |
597 | * kcryptd_io performs the IO submission. | |
598 | * | |
599 | * They must be separated as otherwise the final stages could be | |
600 | * starved by new requests which can block in the first stages due | |
601 | * to memory allocation. | |
1da177e4 | 602 | */ |
6712ecf8 | 603 | static void crypt_endio(struct bio *clone, int error) |
8b004457 | 604 | { |
028867ac | 605 | struct dm_crypt_io *io = clone->bi_private; |
8b004457 | 606 | struct crypt_config *cc = io->target->private; |
ee7a491e | 607 | unsigned rw = bio_data_dir(clone); |
8b004457 | 608 | |
adfe4770 MB |
609 | if (unlikely(!bio_flagged(clone, BIO_UPTODATE) && !error)) |
610 | error = -EIO; | |
611 | ||
8b004457 | 612 | /* |
6712ecf8 | 613 | * free the processed pages |
8b004457 | 614 | */ |
ee7a491e | 615 | if (rw == WRITE) |
644bd2f0 | 616 | crypt_free_buffer_pages(cc, clone); |
8b004457 MB |
617 | |
618 | bio_put(clone); | |
8b004457 | 619 | |
ee7a491e MB |
620 | if (rw == READ && !error) { |
621 | kcryptd_queue_crypt(io); | |
622 | return; | |
623 | } | |
5742fd77 MB |
624 | |
625 | if (unlikely(error)) | |
626 | io->error = error; | |
627 | ||
628 | crypt_dec_pending(io); | |
8b004457 MB |
629 | } |
630 | ||
028867ac | 631 | static void clone_init(struct dm_crypt_io *io, struct bio *clone) |
8b004457 MB |
632 | { |
633 | struct crypt_config *cc = io->target->private; | |
634 | ||
635 | clone->bi_private = io; | |
636 | clone->bi_end_io = crypt_endio; | |
637 | clone->bi_bdev = cc->dev->bdev; | |
638 | clone->bi_rw = io->base_bio->bi_rw; | |
027581f3 | 639 | clone->bi_destructor = dm_crypt_bio_destructor; |
8b004457 MB |
640 | } |
641 | ||
4e4eef64 | 642 | static void kcryptd_io_read(struct dm_crypt_io *io) |
8b004457 MB |
643 | { |
644 | struct crypt_config *cc = io->target->private; | |
645 | struct bio *base_bio = io->base_bio; | |
646 | struct bio *clone; | |
93e605c2 | 647 | |
3e1a8bdd | 648 | crypt_inc_pending(io); |
8b004457 MB |
649 | |
650 | /* | |
651 | * The block layer might modify the bvec array, so always | |
652 | * copy the required bvecs because we need the original | |
653 | * one in order to decrypt the whole bio data *afterwards*. | |
654 | */ | |
6a24c718 | 655 | clone = bio_alloc_bioset(GFP_NOIO, bio_segments(base_bio), cc->bs); |
93e605c2 | 656 | if (unlikely(!clone)) { |
5742fd77 MB |
657 | io->error = -ENOMEM; |
658 | crypt_dec_pending(io); | |
23541d2d | 659 | return; |
93e605c2 | 660 | } |
8b004457 MB |
661 | |
662 | clone_init(io, clone); | |
663 | clone->bi_idx = 0; | |
664 | clone->bi_vcnt = bio_segments(base_bio); | |
665 | clone->bi_size = base_bio->bi_size; | |
0c395b0f | 666 | clone->bi_sector = cc->start + io->sector; |
8b004457 MB |
667 | memcpy(clone->bi_io_vec, bio_iovec(base_bio), |
668 | sizeof(struct bio_vec) * clone->bi_vcnt); | |
8b004457 | 669 | |
93e605c2 | 670 | generic_make_request(clone); |
8b004457 MB |
671 | } |
672 | ||
4e4eef64 MB |
673 | static void kcryptd_io_write(struct dm_crypt_io *io) |
674 | { | |
95497a96 | 675 | struct bio *clone = io->ctx.bio_out; |
95497a96 | 676 | generic_make_request(clone); |
4e4eef64 MB |
677 | } |
678 | ||
395b167c AK |
679 | static void kcryptd_io(struct work_struct *work) |
680 | { | |
681 | struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work); | |
682 | ||
683 | if (bio_data_dir(io->base_bio) == READ) | |
684 | kcryptd_io_read(io); | |
685 | else | |
686 | kcryptd_io_write(io); | |
687 | } | |
688 | ||
689 | static void kcryptd_queue_io(struct dm_crypt_io *io) | |
690 | { | |
691 | struct crypt_config *cc = io->target->private; | |
692 | ||
693 | INIT_WORK(&io->work, kcryptd_io); | |
694 | queue_work(cc->io_queue, &io->work); | |
695 | } | |
696 | ||
95497a96 MB |
697 | static void kcryptd_crypt_write_io_submit(struct dm_crypt_io *io, |
698 | int error, int async) | |
4e4eef64 | 699 | { |
dec1cedf MB |
700 | struct bio *clone = io->ctx.bio_out; |
701 | struct crypt_config *cc = io->target->private; | |
702 | ||
703 | if (unlikely(error < 0)) { | |
704 | crypt_free_buffer_pages(cc, clone); | |
705 | bio_put(clone); | |
706 | io->error = -EIO; | |
6c031f41 | 707 | crypt_dec_pending(io); |
dec1cedf MB |
708 | return; |
709 | } | |
710 | ||
711 | /* crypt_convert should have filled the clone bio */ | |
712 | BUG_ON(io->ctx.idx_out < clone->bi_vcnt); | |
713 | ||
714 | clone->bi_sector = cc->start + io->sector; | |
899c95d3 | 715 | |
95497a96 MB |
716 | if (async) |
717 | kcryptd_queue_io(io); | |
1e37bb8e | 718 | else |
95497a96 | 719 | generic_make_request(clone); |
4e4eef64 MB |
720 | } |
721 | ||
fc5a5e9a | 722 | static void kcryptd_crypt_write_convert(struct dm_crypt_io *io) |
8b004457 MB |
723 | { |
724 | struct crypt_config *cc = io->target->private; | |
8b004457 | 725 | struct bio *clone; |
393b47ef | 726 | struct dm_crypt_io *new_io; |
c8081618 | 727 | int crypt_finished; |
933f01d4 | 728 | unsigned out_of_pages = 0; |
dec1cedf | 729 | unsigned remaining = io->base_bio->bi_size; |
b635b00e | 730 | sector_t sector = io->sector; |
dec1cedf | 731 | int r; |
8b004457 | 732 | |
fc5a5e9a MB |
733 | /* |
734 | * Prevent io from disappearing until this function completes. | |
735 | */ | |
736 | crypt_inc_pending(io); | |
b635b00e | 737 | crypt_convert_init(cc, &io->ctx, NULL, io->base_bio, sector); |
fc5a5e9a | 738 | |
93e605c2 MB |
739 | /* |
740 | * The allocated buffers can be smaller than the whole bio, | |
741 | * so repeat the whole process until all the data can be handled. | |
742 | */ | |
743 | while (remaining) { | |
933f01d4 | 744 | clone = crypt_alloc_buffer(io, remaining, &out_of_pages); |
23541d2d | 745 | if (unlikely(!clone)) { |
5742fd77 | 746 | io->error = -ENOMEM; |
fc5a5e9a | 747 | break; |
23541d2d | 748 | } |
93e605c2 | 749 | |
53017030 MB |
750 | io->ctx.bio_out = clone; |
751 | io->ctx.idx_out = 0; | |
93e605c2 | 752 | |
dec1cedf | 753 | remaining -= clone->bi_size; |
b635b00e | 754 | sector += bio_sectors(clone); |
93e605c2 | 755 | |
4e594098 | 756 | crypt_inc_pending(io); |
dec1cedf | 757 | r = crypt_convert(cc, &io->ctx); |
c8081618 | 758 | crypt_finished = atomic_dec_and_test(&io->ctx.pending); |
f97380bc | 759 | |
c8081618 MB |
760 | /* Encryption was already finished, submit io now */ |
761 | if (crypt_finished) { | |
3a7f6c99 | 762 | kcryptd_crypt_write_io_submit(io, r, 0); |
c8081618 MB |
763 | |
764 | /* | |
765 | * If there was an error, do not try next fragments. | |
766 | * For async, error is processed in async handler. | |
767 | */ | |
6c031f41 | 768 | if (unlikely(r < 0)) |
fc5a5e9a | 769 | break; |
b635b00e MB |
770 | |
771 | io->sector = sector; | |
4e594098 | 772 | } |
93e605c2 | 773 | |
933f01d4 MB |
774 | /* |
775 | * Out of memory -> run queues | |
776 | * But don't wait if split was due to the io size restriction | |
777 | */ | |
778 | if (unlikely(out_of_pages)) | |
98221eb7 | 779 | congestion_wait(WRITE, HZ/100); |
933f01d4 | 780 | |
393b47ef MB |
781 | /* |
782 | * With async crypto it is unsafe to share the crypto context | |
783 | * between fragments, so switch to a new dm_crypt_io structure. | |
784 | */ | |
785 | if (unlikely(!crypt_finished && remaining)) { | |
786 | new_io = crypt_io_alloc(io->target, io->base_bio, | |
787 | sector); | |
788 | crypt_inc_pending(new_io); | |
789 | crypt_convert_init(cc, &new_io->ctx, NULL, | |
790 | io->base_bio, sector); | |
791 | new_io->ctx.idx_in = io->ctx.idx_in; | |
792 | new_io->ctx.offset_in = io->ctx.offset_in; | |
793 | ||
794 | /* | |
795 | * Fragments after the first use the base_io | |
796 | * pending count. | |
797 | */ | |
798 | if (!io->base_io) | |
799 | new_io->base_io = io; | |
800 | else { | |
801 | new_io->base_io = io->base_io; | |
802 | crypt_inc_pending(io->base_io); | |
803 | crypt_dec_pending(io); | |
804 | } | |
805 | ||
806 | io = new_io; | |
807 | } | |
93e605c2 | 808 | } |
899c95d3 MB |
809 | |
810 | crypt_dec_pending(io); | |
84131db6 MB |
811 | } |
812 | ||
4e4eef64 | 813 | static void kcryptd_crypt_read_done(struct dm_crypt_io *io, int error) |
5742fd77 MB |
814 | { |
815 | if (unlikely(error < 0)) | |
816 | io->error = -EIO; | |
817 | ||
818 | crypt_dec_pending(io); | |
819 | } | |
820 | ||
4e4eef64 | 821 | static void kcryptd_crypt_read_convert(struct dm_crypt_io *io) |
8b004457 MB |
822 | { |
823 | struct crypt_config *cc = io->target->private; | |
5742fd77 | 824 | int r = 0; |
1da177e4 | 825 | |
3e1a8bdd | 826 | crypt_inc_pending(io); |
3a7f6c99 | 827 | |
53017030 | 828 | crypt_convert_init(cc, &io->ctx, io->base_bio, io->base_bio, |
0c395b0f | 829 | io->sector); |
1da177e4 | 830 | |
5742fd77 MB |
831 | r = crypt_convert(cc, &io->ctx); |
832 | ||
3f1e9070 | 833 | if (atomic_dec_and_test(&io->ctx.pending)) |
3a7f6c99 MB |
834 | kcryptd_crypt_read_done(io, r); |
835 | ||
836 | crypt_dec_pending(io); | |
1da177e4 LT |
837 | } |
838 | ||
95497a96 MB |
839 | static void kcryptd_async_done(struct crypto_async_request *async_req, |
840 | int error) | |
841 | { | |
b2174eeb HY |
842 | struct dm_crypt_request *dmreq = async_req->data; |
843 | struct convert_context *ctx = dmreq->ctx; | |
95497a96 MB |
844 | struct dm_crypt_io *io = container_of(ctx, struct dm_crypt_io, ctx); |
845 | struct crypt_config *cc = io->target->private; | |
846 | ||
847 | if (error == -EINPROGRESS) { | |
848 | complete(&ctx->restart); | |
849 | return; | |
850 | } | |
851 | ||
b2174eeb | 852 | mempool_free(req_of_dmreq(cc, dmreq), cc->req_pool); |
95497a96 MB |
853 | |
854 | if (!atomic_dec_and_test(&ctx->pending)) | |
855 | return; | |
856 | ||
857 | if (bio_data_dir(io->base_bio) == READ) | |
858 | kcryptd_crypt_read_done(io, error); | |
859 | else | |
860 | kcryptd_crypt_write_io_submit(io, error, 1); | |
861 | } | |
862 | ||
395b167c | 863 | static void kcryptd_crypt(struct work_struct *work) |
1da177e4 | 864 | { |
028867ac | 865 | struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work); |
8b004457 | 866 | |
cabf08e4 | 867 | if (bio_data_dir(io->base_bio) == READ) |
395b167c | 868 | kcryptd_crypt_read_convert(io); |
4e4eef64 | 869 | else |
395b167c | 870 | kcryptd_crypt_write_convert(io); |
cabf08e4 MB |
871 | } |
872 | ||
395b167c | 873 | static void kcryptd_queue_crypt(struct dm_crypt_io *io) |
cabf08e4 | 874 | { |
395b167c | 875 | struct crypt_config *cc = io->target->private; |
cabf08e4 | 876 | |
395b167c AK |
877 | INIT_WORK(&io->work, kcryptd_crypt); |
878 | queue_work(cc->crypt_queue, &io->work); | |
1da177e4 LT |
879 | } |
880 | ||
881 | /* | |
882 | * Decode key from its hex representation | |
883 | */ | |
884 | static int crypt_decode_key(u8 *key, char *hex, unsigned int size) | |
885 | { | |
886 | char buffer[3]; | |
887 | char *endp; | |
888 | unsigned int i; | |
889 | ||
890 | buffer[2] = '\0'; | |
891 | ||
8b004457 | 892 | for (i = 0; i < size; i++) { |
1da177e4 LT |
893 | buffer[0] = *hex++; |
894 | buffer[1] = *hex++; | |
895 | ||
896 | key[i] = (u8)simple_strtoul(buffer, &endp, 16); | |
897 | ||
898 | if (endp != &buffer[2]) | |
899 | return -EINVAL; | |
900 | } | |
901 | ||
902 | if (*hex != '\0') | |
903 | return -EINVAL; | |
904 | ||
905 | return 0; | |
906 | } | |
907 | ||
908 | /* | |
909 | * Encode key into its hex representation | |
910 | */ | |
911 | static void crypt_encode_key(char *hex, u8 *key, unsigned int size) | |
912 | { | |
913 | unsigned int i; | |
914 | ||
8b004457 | 915 | for (i = 0; i < size; i++) { |
1da177e4 LT |
916 | sprintf(hex, "%02x", *key); |
917 | hex += 2; | |
918 | key++; | |
919 | } | |
920 | } | |
921 | ||
e48d4bbf MB |
922 | static int crypt_set_key(struct crypt_config *cc, char *key) |
923 | { | |
924 | unsigned key_size = strlen(key) >> 1; | |
925 | ||
926 | if (cc->key_size && cc->key_size != key_size) | |
927 | return -EINVAL; | |
928 | ||
929 | cc->key_size = key_size; /* initial settings */ | |
930 | ||
931 | if ((!key_size && strcmp(key, "-")) || | |
d469f841 | 932 | (key_size && crypt_decode_key(cc->key, key, key_size) < 0)) |
e48d4bbf MB |
933 | return -EINVAL; |
934 | ||
935 | set_bit(DM_CRYPT_KEY_VALID, &cc->flags); | |
936 | ||
937 | return 0; | |
938 | } | |
939 | ||
940 | static int crypt_wipe_key(struct crypt_config *cc) | |
941 | { | |
942 | clear_bit(DM_CRYPT_KEY_VALID, &cc->flags); | |
943 | memset(&cc->key, 0, cc->key_size * sizeof(u8)); | |
944 | return 0; | |
945 | } | |
946 | ||
1da177e4 LT |
947 | /* |
948 | * Construct an encryption mapping: | |
949 | * <cipher> <key> <iv_offset> <dev_path> <start> | |
950 | */ | |
951 | static int crypt_ctr(struct dm_target *ti, unsigned int argc, char **argv) | |
952 | { | |
953 | struct crypt_config *cc; | |
3a7f6c99 | 954 | struct crypto_ablkcipher *tfm; |
1da177e4 LT |
955 | char *tmp; |
956 | char *cipher; | |
957 | char *chainmode; | |
958 | char *ivmode; | |
959 | char *ivopts; | |
1da177e4 | 960 | unsigned int key_size; |
4ee218cd | 961 | unsigned long long tmpll; |
1da177e4 LT |
962 | |
963 | if (argc != 5) { | |
72d94861 | 964 | ti->error = "Not enough arguments"; |
1da177e4 LT |
965 | return -EINVAL; |
966 | } | |
967 | ||
968 | tmp = argv[0]; | |
969 | cipher = strsep(&tmp, "-"); | |
970 | chainmode = strsep(&tmp, "-"); | |
971 | ivopts = strsep(&tmp, "-"); | |
972 | ivmode = strsep(&ivopts, ":"); | |
973 | ||
974 | if (tmp) | |
72d94861 | 975 | DMWARN("Unexpected additional cipher options"); |
1da177e4 LT |
976 | |
977 | key_size = strlen(argv[1]) >> 1; | |
978 | ||
e48d4bbf | 979 | cc = kzalloc(sizeof(*cc) + key_size * sizeof(u8), GFP_KERNEL); |
1da177e4 LT |
980 | if (cc == NULL) { |
981 | ti->error = | |
72d94861 | 982 | "Cannot allocate transparent encryption context"; |
1da177e4 LT |
983 | return -ENOMEM; |
984 | } | |
985 | ||
e48d4bbf | 986 | if (crypt_set_key(cc, argv[1])) { |
72d94861 | 987 | ti->error = "Error decoding key"; |
636d5786 | 988 | goto bad_cipher; |
1da177e4 LT |
989 | } |
990 | ||
991 | /* Compatiblity mode for old dm-crypt cipher strings */ | |
992 | if (!chainmode || (strcmp(chainmode, "plain") == 0 && !ivmode)) { | |
993 | chainmode = "cbc"; | |
994 | ivmode = "plain"; | |
995 | } | |
996 | ||
d1806f6a HX |
997 | if (strcmp(chainmode, "ecb") && !ivmode) { |
998 | ti->error = "This chaining mode requires an IV mechanism"; | |
636d5786 | 999 | goto bad_cipher; |
1da177e4 LT |
1000 | } |
1001 | ||
d469f841 MB |
1002 | if (snprintf(cc->cipher, CRYPTO_MAX_ALG_NAME, "%s(%s)", |
1003 | chainmode, cipher) >= CRYPTO_MAX_ALG_NAME) { | |
d1806f6a | 1004 | ti->error = "Chain mode + cipher name is too long"; |
636d5786 | 1005 | goto bad_cipher; |
1da177e4 LT |
1006 | } |
1007 | ||
3a7f6c99 | 1008 | tfm = crypto_alloc_ablkcipher(cc->cipher, 0, 0); |
d1806f6a | 1009 | if (IS_ERR(tfm)) { |
72d94861 | 1010 | ti->error = "Error allocating crypto tfm"; |
636d5786 | 1011 | goto bad_cipher; |
1da177e4 | 1012 | } |
1da177e4 | 1013 | |
d1806f6a HX |
1014 | strcpy(cc->cipher, cipher); |
1015 | strcpy(cc->chainmode, chainmode); | |
1da177e4 LT |
1016 | cc->tfm = tfm; |
1017 | ||
1018 | /* | |
48527fa7 | 1019 | * Choose ivmode. Valid modes: "plain", "essiv:<esshash>", "benbi". |
1da177e4 LT |
1020 | * See comments at iv code |
1021 | */ | |
1022 | ||
1023 | if (ivmode == NULL) | |
1024 | cc->iv_gen_ops = NULL; | |
1025 | else if (strcmp(ivmode, "plain") == 0) | |
1026 | cc->iv_gen_ops = &crypt_iv_plain_ops; | |
1027 | else if (strcmp(ivmode, "essiv") == 0) | |
1028 | cc->iv_gen_ops = &crypt_iv_essiv_ops; | |
48527fa7 RS |
1029 | else if (strcmp(ivmode, "benbi") == 0) |
1030 | cc->iv_gen_ops = &crypt_iv_benbi_ops; | |
46b47730 LN |
1031 | else if (strcmp(ivmode, "null") == 0) |
1032 | cc->iv_gen_ops = &crypt_iv_null_ops; | |
1da177e4 | 1033 | else { |
72d94861 | 1034 | ti->error = "Invalid IV mode"; |
636d5786 | 1035 | goto bad_ivmode; |
1da177e4 LT |
1036 | } |
1037 | ||
1038 | if (cc->iv_gen_ops && cc->iv_gen_ops->ctr && | |
1039 | cc->iv_gen_ops->ctr(cc, ti, ivopts) < 0) | |
636d5786 | 1040 | goto bad_ivmode; |
1da177e4 | 1041 | |
3a7f6c99 | 1042 | cc->iv_size = crypto_ablkcipher_ivsize(tfm); |
d1806f6a | 1043 | if (cc->iv_size) |
1da177e4 | 1044 | /* at least a 64 bit sector number should fit in our buffer */ |
d1806f6a | 1045 | cc->iv_size = max(cc->iv_size, |
d469f841 | 1046 | (unsigned int)(sizeof(u64) / sizeof(u8))); |
1da177e4 | 1047 | else { |
1da177e4 | 1048 | if (cc->iv_gen_ops) { |
72d94861 | 1049 | DMWARN("Selected cipher does not support IVs"); |
1da177e4 LT |
1050 | if (cc->iv_gen_ops->dtr) |
1051 | cc->iv_gen_ops->dtr(cc); | |
1052 | cc->iv_gen_ops = NULL; | |
1053 | } | |
1054 | } | |
1055 | ||
93d2341c | 1056 | cc->io_pool = mempool_create_slab_pool(MIN_IOS, _crypt_io_pool); |
1da177e4 | 1057 | if (!cc->io_pool) { |
72d94861 | 1058 | ti->error = "Cannot allocate crypt io mempool"; |
636d5786 | 1059 | goto bad_slab_pool; |
1da177e4 LT |
1060 | } |
1061 | ||
ddd42edf | 1062 | cc->dmreq_start = sizeof(struct ablkcipher_request); |
3a7f6c99 | 1063 | cc->dmreq_start += crypto_ablkcipher_reqsize(tfm); |
ddd42edf | 1064 | cc->dmreq_start = ALIGN(cc->dmreq_start, crypto_tfm_ctx_alignment()); |
3a7f6c99 MB |
1065 | cc->dmreq_start += crypto_ablkcipher_alignmask(tfm) & |
1066 | ~(crypto_tfm_ctx_alignment() - 1); | |
ddd42edf MB |
1067 | |
1068 | cc->req_pool = mempool_create_kmalloc_pool(MIN_IOS, cc->dmreq_start + | |
1069 | sizeof(struct dm_crypt_request) + cc->iv_size); | |
1070 | if (!cc->req_pool) { | |
1071 | ti->error = "Cannot allocate crypt request mempool"; | |
1072 | goto bad_req_pool; | |
1073 | } | |
1074 | cc->req = NULL; | |
1075 | ||
a19b27ce | 1076 | cc->page_pool = mempool_create_page_pool(MIN_POOL_PAGES, 0); |
1da177e4 | 1077 | if (!cc->page_pool) { |
72d94861 | 1078 | ti->error = "Cannot allocate page mempool"; |
636d5786 | 1079 | goto bad_page_pool; |
1da177e4 LT |
1080 | } |
1081 | ||
bb799ca0 | 1082 | cc->bs = bioset_create(MIN_IOS, 0); |
6a24c718 MB |
1083 | if (!cc->bs) { |
1084 | ti->error = "Cannot allocate crypt bioset"; | |
1085 | goto bad_bs; | |
1086 | } | |
1087 | ||
3a7f6c99 | 1088 | if (crypto_ablkcipher_setkey(tfm, cc->key, key_size) < 0) { |
72d94861 | 1089 | ti->error = "Error setting key"; |
636d5786 | 1090 | goto bad_device; |
1da177e4 LT |
1091 | } |
1092 | ||
4ee218cd | 1093 | if (sscanf(argv[2], "%llu", &tmpll) != 1) { |
72d94861 | 1094 | ti->error = "Invalid iv_offset sector"; |
636d5786 | 1095 | goto bad_device; |
1da177e4 | 1096 | } |
4ee218cd | 1097 | cc->iv_offset = tmpll; |
1da177e4 | 1098 | |
4ee218cd | 1099 | if (sscanf(argv[4], "%llu", &tmpll) != 1) { |
72d94861 | 1100 | ti->error = "Invalid device sector"; |
636d5786 | 1101 | goto bad_device; |
1da177e4 | 1102 | } |
4ee218cd | 1103 | cc->start = tmpll; |
1da177e4 LT |
1104 | |
1105 | if (dm_get_device(ti, argv[3], cc->start, ti->len, | |
d469f841 | 1106 | dm_table_get_mode(ti->table), &cc->dev)) { |
72d94861 | 1107 | ti->error = "Device lookup failed"; |
636d5786 | 1108 | goto bad_device; |
1da177e4 LT |
1109 | } |
1110 | ||
1111 | if (ivmode && cc->iv_gen_ops) { | |
1112 | if (ivopts) | |
1113 | *(ivopts - 1) = ':'; | |
1114 | cc->iv_mode = kmalloc(strlen(ivmode) + 1, GFP_KERNEL); | |
1115 | if (!cc->iv_mode) { | |
72d94861 | 1116 | ti->error = "Error kmallocing iv_mode string"; |
636d5786 | 1117 | goto bad_ivmode_string; |
1da177e4 LT |
1118 | } |
1119 | strcpy(cc->iv_mode, ivmode); | |
1120 | } else | |
1121 | cc->iv_mode = NULL; | |
1122 | ||
cabf08e4 MB |
1123 | cc->io_queue = create_singlethread_workqueue("kcryptd_io"); |
1124 | if (!cc->io_queue) { | |
1125 | ti->error = "Couldn't create kcryptd io queue"; | |
1126 | goto bad_io_queue; | |
1127 | } | |
1128 | ||
1129 | cc->crypt_queue = create_singlethread_workqueue("kcryptd"); | |
1130 | if (!cc->crypt_queue) { | |
9934a8be | 1131 | ti->error = "Couldn't create kcryptd queue"; |
cabf08e4 | 1132 | goto bad_crypt_queue; |
9934a8be MB |
1133 | } |
1134 | ||
647c7db1 | 1135 | ti->num_flush_requests = 1; |
1da177e4 LT |
1136 | ti->private = cc; |
1137 | return 0; | |
1138 | ||
cabf08e4 MB |
1139 | bad_crypt_queue: |
1140 | destroy_workqueue(cc->io_queue); | |
1141 | bad_io_queue: | |
9934a8be | 1142 | kfree(cc->iv_mode); |
636d5786 | 1143 | bad_ivmode_string: |
55b42c5a | 1144 | dm_put_device(ti, cc->dev); |
636d5786 | 1145 | bad_device: |
6a24c718 MB |
1146 | bioset_free(cc->bs); |
1147 | bad_bs: | |
1da177e4 | 1148 | mempool_destroy(cc->page_pool); |
636d5786 | 1149 | bad_page_pool: |
ddd42edf MB |
1150 | mempool_destroy(cc->req_pool); |
1151 | bad_req_pool: | |
1da177e4 | 1152 | mempool_destroy(cc->io_pool); |
636d5786 | 1153 | bad_slab_pool: |
1da177e4 LT |
1154 | if (cc->iv_gen_ops && cc->iv_gen_ops->dtr) |
1155 | cc->iv_gen_ops->dtr(cc); | |
636d5786 | 1156 | bad_ivmode: |
3a7f6c99 | 1157 | crypto_free_ablkcipher(tfm); |
636d5786 | 1158 | bad_cipher: |
9d3520a3 | 1159 | /* Must zero key material before freeing */ |
b81d6cf7 | 1160 | kzfree(cc); |
1da177e4 LT |
1161 | return -EINVAL; |
1162 | } | |
1163 | ||
1164 | static void crypt_dtr(struct dm_target *ti) | |
1165 | { | |
1166 | struct crypt_config *cc = (struct crypt_config *) ti->private; | |
1167 | ||
cabf08e4 MB |
1168 | destroy_workqueue(cc->io_queue); |
1169 | destroy_workqueue(cc->crypt_queue); | |
80b16c19 | 1170 | |
ddd42edf MB |
1171 | if (cc->req) |
1172 | mempool_free(cc->req, cc->req_pool); | |
1173 | ||
6a24c718 | 1174 | bioset_free(cc->bs); |
1da177e4 | 1175 | mempool_destroy(cc->page_pool); |
ddd42edf | 1176 | mempool_destroy(cc->req_pool); |
1da177e4 LT |
1177 | mempool_destroy(cc->io_pool); |
1178 | ||
990a8baf | 1179 | kfree(cc->iv_mode); |
1da177e4 LT |
1180 | if (cc->iv_gen_ops && cc->iv_gen_ops->dtr) |
1181 | cc->iv_gen_ops->dtr(cc); | |
3a7f6c99 | 1182 | crypto_free_ablkcipher(cc->tfm); |
1da177e4 | 1183 | dm_put_device(ti, cc->dev); |
9d3520a3 SR |
1184 | |
1185 | /* Must zero key material before freeing */ | |
b81d6cf7 | 1186 | kzfree(cc); |
1da177e4 LT |
1187 | } |
1188 | ||
1da177e4 LT |
1189 | static int crypt_map(struct dm_target *ti, struct bio *bio, |
1190 | union map_info *map_context) | |
1191 | { | |
028867ac | 1192 | struct dm_crypt_io *io; |
647c7db1 MP |
1193 | struct crypt_config *cc; |
1194 | ||
1195 | if (unlikely(bio_empty_barrier(bio))) { | |
1196 | cc = ti->private; | |
1197 | bio->bi_bdev = cc->dev->bdev; | |
1198 | return DM_MAPIO_REMAPPED; | |
1199 | } | |
1da177e4 | 1200 | |
dc440d1e | 1201 | io = crypt_io_alloc(ti, bio, bio->bi_sector - ti->begin); |
cabf08e4 MB |
1202 | |
1203 | if (bio_data_dir(io->base_bio) == READ) | |
1204 | kcryptd_queue_io(io); | |
1205 | else | |
1206 | kcryptd_queue_crypt(io); | |
1da177e4 | 1207 | |
d2a7ad29 | 1208 | return DM_MAPIO_SUBMITTED; |
1da177e4 LT |
1209 | } |
1210 | ||
1211 | static int crypt_status(struct dm_target *ti, status_type_t type, | |
1212 | char *result, unsigned int maxlen) | |
1213 | { | |
1214 | struct crypt_config *cc = (struct crypt_config *) ti->private; | |
1da177e4 LT |
1215 | unsigned int sz = 0; |
1216 | ||
1217 | switch (type) { | |
1218 | case STATUSTYPE_INFO: | |
1219 | result[0] = '\0'; | |
1220 | break; | |
1221 | ||
1222 | case STATUSTYPE_TABLE: | |
1da177e4 | 1223 | if (cc->iv_mode) |
37af6560 CS |
1224 | DMEMIT("%s-%s-%s ", cc->cipher, cc->chainmode, |
1225 | cc->iv_mode); | |
1da177e4 | 1226 | else |
37af6560 | 1227 | DMEMIT("%s-%s ", cc->cipher, cc->chainmode); |
1da177e4 LT |
1228 | |
1229 | if (cc->key_size > 0) { | |
1230 | if ((maxlen - sz) < ((cc->key_size << 1) + 1)) | |
1231 | return -ENOMEM; | |
1232 | ||
1233 | crypt_encode_key(result + sz, cc->key, cc->key_size); | |
1234 | sz += cc->key_size << 1; | |
1235 | } else { | |
1236 | if (sz >= maxlen) | |
1237 | return -ENOMEM; | |
1238 | result[sz++] = '-'; | |
1239 | } | |
1240 | ||
4ee218cd AM |
1241 | DMEMIT(" %llu %s %llu", (unsigned long long)cc->iv_offset, |
1242 | cc->dev->name, (unsigned long long)cc->start); | |
1da177e4 LT |
1243 | break; |
1244 | } | |
1245 | return 0; | |
1246 | } | |
1247 | ||
e48d4bbf MB |
1248 | static void crypt_postsuspend(struct dm_target *ti) |
1249 | { | |
1250 | struct crypt_config *cc = ti->private; | |
1251 | ||
1252 | set_bit(DM_CRYPT_SUSPENDED, &cc->flags); | |
1253 | } | |
1254 | ||
1255 | static int crypt_preresume(struct dm_target *ti) | |
1256 | { | |
1257 | struct crypt_config *cc = ti->private; | |
1258 | ||
1259 | if (!test_bit(DM_CRYPT_KEY_VALID, &cc->flags)) { | |
1260 | DMERR("aborting resume - crypt key is not set."); | |
1261 | return -EAGAIN; | |
1262 | } | |
1263 | ||
1264 | return 0; | |
1265 | } | |
1266 | ||
1267 | static void crypt_resume(struct dm_target *ti) | |
1268 | { | |
1269 | struct crypt_config *cc = ti->private; | |
1270 | ||
1271 | clear_bit(DM_CRYPT_SUSPENDED, &cc->flags); | |
1272 | } | |
1273 | ||
1274 | /* Message interface | |
1275 | * key set <key> | |
1276 | * key wipe | |
1277 | */ | |
1278 | static int crypt_message(struct dm_target *ti, unsigned argc, char **argv) | |
1279 | { | |
1280 | struct crypt_config *cc = ti->private; | |
1281 | ||
1282 | if (argc < 2) | |
1283 | goto error; | |
1284 | ||
1285 | if (!strnicmp(argv[0], MESG_STR("key"))) { | |
1286 | if (!test_bit(DM_CRYPT_SUSPENDED, &cc->flags)) { | |
1287 | DMWARN("not suspended during key manipulation."); | |
1288 | return -EINVAL; | |
1289 | } | |
1290 | if (argc == 3 && !strnicmp(argv[1], MESG_STR("set"))) | |
1291 | return crypt_set_key(cc, argv[2]); | |
1292 | if (argc == 2 && !strnicmp(argv[1], MESG_STR("wipe"))) | |
1293 | return crypt_wipe_key(cc); | |
1294 | } | |
1295 | ||
1296 | error: | |
1297 | DMWARN("unrecognised message received."); | |
1298 | return -EINVAL; | |
1299 | } | |
1300 | ||
d41e26b9 MB |
1301 | static int crypt_merge(struct dm_target *ti, struct bvec_merge_data *bvm, |
1302 | struct bio_vec *biovec, int max_size) | |
1303 | { | |
1304 | struct crypt_config *cc = ti->private; | |
1305 | struct request_queue *q = bdev_get_queue(cc->dev->bdev); | |
1306 | ||
1307 | if (!q->merge_bvec_fn) | |
1308 | return max_size; | |
1309 | ||
1310 | bvm->bi_bdev = cc->dev->bdev; | |
1311 | bvm->bi_sector = cc->start + bvm->bi_sector - ti->begin; | |
1312 | ||
1313 | return min(max_size, q->merge_bvec_fn(q, bvm, biovec)); | |
1314 | } | |
1315 | ||
1da177e4 LT |
1316 | static struct target_type crypt_target = { |
1317 | .name = "crypt", | |
d41e26b9 | 1318 | .version= {1, 6, 0}, |
1da177e4 LT |
1319 | .module = THIS_MODULE, |
1320 | .ctr = crypt_ctr, | |
1321 | .dtr = crypt_dtr, | |
1322 | .map = crypt_map, | |
1323 | .status = crypt_status, | |
e48d4bbf MB |
1324 | .postsuspend = crypt_postsuspend, |
1325 | .preresume = crypt_preresume, | |
1326 | .resume = crypt_resume, | |
1327 | .message = crypt_message, | |
d41e26b9 | 1328 | .merge = crypt_merge, |
1da177e4 LT |
1329 | }; |
1330 | ||
1331 | static int __init dm_crypt_init(void) | |
1332 | { | |
1333 | int r; | |
1334 | ||
028867ac | 1335 | _crypt_io_pool = KMEM_CACHE(dm_crypt_io, 0); |
1da177e4 LT |
1336 | if (!_crypt_io_pool) |
1337 | return -ENOMEM; | |
1338 | ||
1da177e4 LT |
1339 | r = dm_register_target(&crypt_target); |
1340 | if (r < 0) { | |
72d94861 | 1341 | DMERR("register failed %d", r); |
9934a8be | 1342 | kmem_cache_destroy(_crypt_io_pool); |
1da177e4 LT |
1343 | } |
1344 | ||
1da177e4 LT |
1345 | return r; |
1346 | } | |
1347 | ||
1348 | static void __exit dm_crypt_exit(void) | |
1349 | { | |
10d3bd09 | 1350 | dm_unregister_target(&crypt_target); |
1da177e4 LT |
1351 | kmem_cache_destroy(_crypt_io_pool); |
1352 | } | |
1353 | ||
1354 | module_init(dm_crypt_init); | |
1355 | module_exit(dm_crypt_exit); | |
1356 | ||
1357 | MODULE_AUTHOR("Christophe Saout <christophe@saout.de>"); | |
1358 | MODULE_DESCRIPTION(DM_NAME " target for transparent encryption / decryption"); | |
1359 | MODULE_LICENSE("GPL"); |